The goal of this research is to provide a molecular basis for understanding the mechanisms for invasiveness of Candida albicans in AIDS patients. The research will start with the relatively clear fact that C. albicans, must adhere to and colonize cells as a stage in establishing an infection. We will use two approaches: (1) a study of mutants that have lost the ability to adhere to animal cells and are subsequently non-pathogenic, and (2) a study of a germ tube-specific protein as a means of understanding the role germ tube penetration plays in invasiveness. We will use gene cloning techniques to study factors that affect the expression of these properties of invasiveness.